Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/lib/crc-t10dif.c b/lib/crc-t10dif.c
index c9acf1c..1ed2ed4 100644
--- a/lib/crc-t10dif.c
+++ b/lib/crc-t10dif.c
@@ -17,7 +17,7 @@
 #include <linux/notifier.h>
 
 static struct crypto_shash __rcu *crct10dif_tfm;
-static struct static_key crct10dif_fallback __read_mostly;
+static DEFINE_STATIC_KEY_TRUE(crct10dif_fallback);
 static DEFINE_MUTEX(crc_t10dif_mutex);
 static struct work_struct crct10dif_rehash_work;
 
@@ -26,12 +26,11 @@
 	struct crypto_alg *alg = data;
 
 	if (val != CRYPTO_MSG_ALG_LOADED ||
-	    static_key_false(&crct10dif_fallback) ||
-	    strncmp(alg->cra_name, CRC_T10DIF_STRING, strlen(CRC_T10DIF_STRING)))
-		return 0;
+	    strcmp(alg->cra_name, CRC_T10DIF_STRING))
+		return NOTIFY_DONE;
 
 	schedule_work(&crct10dif_rehash_work);
-	return 0;
+	return NOTIFY_OK;
 }
 
 static void crc_t10dif_rehash(struct work_struct *work)
@@ -41,11 +40,7 @@
 	mutex_lock(&crc_t10dif_mutex);
 	old = rcu_dereference_protected(crct10dif_tfm,
 					lockdep_is_held(&crc_t10dif_mutex));
-	if (!old) {
-		mutex_unlock(&crc_t10dif_mutex);
-		return;
-	}
-	new = crypto_alloc_shash("crct10dif", 0, 0);
+	new = crypto_alloc_shash(CRC_T10DIF_STRING, 0, 0);
 	if (IS_ERR(new)) {
 		mutex_unlock(&crc_t10dif_mutex);
 		return;
@@ -53,8 +48,12 @@
 	rcu_assign_pointer(crct10dif_tfm, new);
 	mutex_unlock(&crc_t10dif_mutex);
 
-	synchronize_rcu();
-	crypto_free_shash(old);
+	if (old) {
+		synchronize_rcu();
+		crypto_free_shash(old);
+	} else {
+		static_branch_disable(&crct10dif_fallback);
+	}
 }
 
 static struct notifier_block crc_t10dif_nb = {
@@ -65,23 +64,22 @@
 {
 	struct {
 		struct shash_desc shash;
-		char ctx[2];
+		__u16 crc;
 	} desc;
 	int err;
 
-	if (static_key_false(&crct10dif_fallback))
+	if (static_branch_unlikely(&crct10dif_fallback))
 		return crc_t10dif_generic(crc, buffer, len);
 
 	rcu_read_lock();
 	desc.shash.tfm = rcu_dereference(crct10dif_tfm);
-	*(__u16 *)desc.ctx = crc;
-
+	desc.crc = crc;
 	err = crypto_shash_update(&desc.shash, buffer, len);
 	rcu_read_unlock();
 
 	BUG_ON(err);
 
-	return *(__u16 *)desc.ctx;
+	return desc.crc;
 }
 EXPORT_SYMBOL(crc_t10dif_update);
 
@@ -93,18 +91,9 @@
 
 static int __init crc_t10dif_mod_init(void)
 {
-	struct crypto_shash *tfm;
-
 	INIT_WORK(&crct10dif_rehash_work, crc_t10dif_rehash);
 	crypto_register_notifier(&crc_t10dif_nb);
-	mutex_lock(&crc_t10dif_mutex);
-	tfm = crypto_alloc_shash("crct10dif", 0, 0);
-	if (IS_ERR(tfm)) {
-		static_key_slow_inc(&crct10dif_fallback);
-		tfm = NULL;
-	}
-	RCU_INIT_POINTER(crct10dif_tfm, tfm);
-	mutex_unlock(&crc_t10dif_mutex);
+	crc_t10dif_rehash(&crct10dif_rehash_work);
 	return 0;
 }
 
@@ -121,30 +110,22 @@
 static int crc_t10dif_transform_show(char *buffer, const struct kernel_param *kp)
 {
 	struct crypto_shash *tfm;
-	const char *name;
 	int len;
 
-	if (static_key_false(&crct10dif_fallback))
+	if (static_branch_unlikely(&crct10dif_fallback))
 		return sprintf(buffer, "fallback\n");
 
 	rcu_read_lock();
 	tfm = rcu_dereference(crct10dif_tfm);
-	if (!tfm) {
-		len = sprintf(buffer, "init\n");
-		goto unlock;
-	}
-
-	name = crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
-	len = sprintf(buffer, "%s\n", name);
-
-unlock:
+	len = snprintf(buffer, PAGE_SIZE, "%s\n",
+		       crypto_shash_driver_name(tfm));
 	rcu_read_unlock();
 
 	return len;
 }
 
-module_param_call(transform, NULL, crc_t10dif_transform_show, NULL, 0644);
+module_param_call(transform, NULL, crc_t10dif_transform_show, NULL, 0444);
 
-MODULE_DESCRIPTION("T10 DIF CRC calculation");
+MODULE_DESCRIPTION("T10 DIF CRC calculation (library API)");
 MODULE_LICENSE("GPL");
 MODULE_SOFTDEP("pre: crct10dif");